Process and apparatus for treating oils.



*0. C. SWAN. PROCESS AND APPARATUS FOR TREATING 0|LS.-

1,250,526. APPLICATION FILEDIJUNE Il. 191?. l Dec. 18

2 SHEETS-SHEET lf I, ,E f/s.

52 l J3 n o. c. SWAN. l PROCESS AND APPARATUS FOR TREATING OILS. APPLICATION FILED JUNE II, 191?.

1,250,526. Y A Patented De@.18,1912`1 2 SHEETS-SHEET 2. 7d /0.

UNTTD STATES PATENT carica.. y

OLIVER C. SWAN, OF DENVER, COLORADO, ASSIGNOR T0 THE SWAN PROCESS OIL A COMPANY, OF DENVER, COLORADO, A CORPORATION OF COLORADO.

PROCESS AND.APPARATUS FORTREATIN G OILS.

specification of Letters Patent. Patented Dec. 18, 1917.

Application led June 11, 1917. Serial No. 174,023.

able others skilled Ain the art to which it ap pertains to make and use the same. Y

This invention relates to an improved process and apparatus for treating oils, and more particularly lubricating oils th-at have been used and are generally allowed to go to waste.

While my present invention is not necessarily limited, in its application, to the treatment of any specific nature of lubricating oils, or their source of supply, still in the following specification I have deemed it desirable to referto this particular eld of usefulness by way of illustration.

Even during'this era of intensive conserv-ation of ordinary waste values, enormous losses, almost incredible, are annually sustained from the waste of the heavy viscous lubricating oils, .the refuse from the cylinders of internal combustion engines and other lubricating sources.

Forinstance, theuse'd oils drained from tlie crank eases-of gasolene engines, besides being densely discolored and malodorous, are more or less'gummy and heavily char ed with unused gasolene, 'carbon in suspension and other foreign substances, manifestly deleterious, in that state, for use as a lubricant. The same is largely true with other used lubricating oils from other sources, wherein they are heavily -laden with dross impurities, and even in unrefinedcrude oils these objectionable impurities have to be eliminated.

With systems as heretofore generally employed for purification purposes, it isbelieved to be impracticable to entirely eliminate these impurities by the ordinary methods ofliiltratio'n.

The primary object of the present invention is to more satisfactorily treat these heavy viscous oils, and more particularly to vreclaim the otherwise discarded refuse oils, heretofore referred to, by removing therefrom their organic and vinorganic impurities and also their volatile constituents deleterious to the most effective uses of lubrication, thus restoring the impure oils to their normal or even improved conditions.

In the process and apparatus disclosed in a former application, Serial No. 7 9,680, led February QlLlQI, the substantially successful reclamation of these used oils was ac.

complished in part by the introduction therein of a harmless treating agent, such as kieselguhr, for preparing the same en masse or as a conglomerate mixture, functioning for more effective filtration.

In the present application, I still employ my former method in substance, but in addition I have introdueed other beneficial steps in themethod of treatment, all of which will hereinafter appear in detail, the

particular .steps and .features of novelty being succinctly specified and set forth iii the appended claims.`

In fully disclosing the invention, I will now lirst refer to the accompanying drawings, embodying my improved apparatus or system Vfor carrying out the process, in which drawings like parts'are designated by the the several same reference characters in vlews, of Wluch* Figure 1, is an elevational view, illustrating diagrammatically a systematic arrangement for carrying out the process, the receivlng tank for the waste impure oils, being vshown in vertical section, and partly broken away; and

Fig. 2, 1s an enlarged v1ew of a slightly different arrangement of the treating tank,

flotation separator and pressure filter, relatively to eac-h other, the treating tank and dotation separator being shown in vertical longitudinal seetlon, and the pressure filter in broken away elevation and partly in section.

To avoid a stretched out illustrationen several sheets ofdrawings, the system is simp ly shown diagrammatically in comprehensive yet compact arrangement, vith the several elements disposed in proper sequential t, order, but in actual practice it will be understood that an installed plant would preferably occupy the several `floors of a building, and the piping lines varied accordingly. The flow of oil through the various steps of the process is accomplished either by avitation or through the agency of sultable pumps, orpby both methods conjointly, as

desired.

cocks, etc.

Briefly stating first the several tank or container elements of the system, A desig-y natos a receiving tank for the impure oils to be treated, il one/of a series of heated clarifying tanks or defecators, C a flotation separator, D a treating tank, E a'mixing receptacle for the treating agent, and l? a filter press or other suitable pressure filter, having the usual filter frames, the foregoing elements functioning to clarify and purify the oil prior to further treatment by distillation, which latter forms an important step in the present process.

G designates one or more. clear oil container tanks, H one of a series of clear oil still supply tanks, K the oil still, L a condenser, lvl a catch-all or vapor trap, N one of a series of residual oil storage tanks, and D and l1", respectively, designate a treating tank and pressure filter, for further treating and refiltering the more or less purified oil after its volatile constituents` have been distilled off. A

The several elements mentioned are suitably coupled up by various pipe lines and branch pipes, pumps and controlling valves being supplied, where needed, but as these equipment fittings are so numerous, and as their general arrangement and functioning are fairly obvious from the drawings, it would only result in unnecessary repetition to specify them in detailed connection at this point, as they will be fully referred to by reference characters in the description of the operation of the system, in carrying out the steps of the process.

l/Vhere desirable, the various receptacles are provided with heating coils, primarily for increasing the fluidity of the heavy oils, illustrated only, at 30, in the sectional View of the treating tank D, Fig. 2. Similarly they may be equipped where neededv with the usual appurtenances, not shown, such as thermometers, water and oil gages, relief valves, sight glasses, peep-holes, sampling Also valve controlled outlets 3l may be employed for drawing olf sediment and for washing out purposes, and may be coupled up with a waste drainage pipe The receiving tank or tanks A are preferably provided with a strainer or grating S8 to initially screen olf Aany contained coarse, impurities, in the impure oils, liable to injure the pumps or system. These tanks are in the nature of sump tanks, sunk to a level with the floor, so 'that barrels of oil may be readily rolled thereover and discharged.

rEhe defecators which a defecating agent may be introduced, when needed, and are suitably heated in any way, shown conventionally by an internal steam coil 34.

The preferred construction of the water flotation separator C is illustrated in the sectional view, in which the tankisrprovided ytop of which cup B are open tanks,'intol filtered oil.

with an inlet pipe 35, which may serve both as a water and oil inlet, and with an outlet water pipe 36. The bottom of the tank may also have the inclining baille plates 37, for deflect-ing the heavy precipitated impurities. 38 designates a shallow upwardly disposed vertical baille plate and 39 a deeper downwardly disposed one, the latter providing, with the former and with the end wall of the tank, a channel 40. for directing the excess water to the waste overflow 4l, thencethrough thc outlet water pipe 36 to a sewer or otherwise. 42 is a collecting trough or cup, forthe overflow of floated oil, the open is disposed slightly above the level of the water overflow 415 The bottom ol the cup may have an elbow fitting 43 coupled with the oil outlet pipe 44.

'lhe tank D is adapted to receive the oil to be treated and also a certain harmless treating agent, in the nature of an inert absorbent medium as hereinafter referred to. The oil may be introduced .into the tank D, after passing through the water flotation separator' C, as shown in Fig. 1,' or the rela- 90 tive positions of these tanks may be reversed as in Fig. 2.

Any suitable provision is made for agitating the contents ofthe tank D to cause a thorough commingling of the oil and treat- 95 ing agent as a conglomerate freely flowing mass. While not so limited this is conveniently shown by the stirrers or agitator blades 45, mounted on a rotary shaft driven by any suitable means, conventionally desiguatcd hy the band pulley 46.

The treating agent might be directly introduced intol the tank D, but as a convenient expedient .it is desirable to employ the mixing receptacle E, in which the treatin@ loa agent isl first mixed with clean oil an caused to flow into the treating tank in pr0- porticnate amounts as desired.

The details'of this mixing receptacle are immaterial, any suitable agitating means being provided, indicated conventionally as comprising rotatably mounted stirrers 47, shown in dotted lines, driven by gearing 48.

After washing and treating, or reversely treating and washing the oil, the conglomcrate mass of the oil and treating agent is, passed through the first Vfilter element of tie system. This filter element F may he either the usualifilter press, 4or as shown in Fig. 2, in detail, a pressure filter of the well known. type, employing replaceable bag covered frames. In Fig. 2, 49 designates the readily removable and replaceable hollow filter frames, having wire gauze facings 50, which frames are enveloped by the filter cloth bags 12e 51. The tops of the frames provided a clear oil space, i discharging through the drip speuts 52, into the elongated tre-ugh 53, having an outlet connection for the purified The details of the clear oil containers `G, the still supply tanks H, and the lresidual oil storage tanks N, are immaterial, they simply being open tanks, preferably provided with heating coils.

Also the specific type of still K, While of considerable importance itself in more efficiently carrying out ythe process, is for a separate invention requiring no detailed description or illustration in so far as the Abroad steps of the process are concerned. It may not be amiss to state briefly, however, that it is of a type to prevent what is known in the art as,cracking distillation, having upper steam jacketedchambers to maintainthe top of the still at the same or even a higher temperature than the heated oil chamber at 4the bottom. The details of this preferred form of still are fully disclosed in my co-pending application for oil stills, Se-

rial N o. 165,240, as is also the vapor trap M, which is simply located in the vapor line 54 leading to the coil or worm 55 of the condenser L, its aim being to trap any sprays of oil entrained with Ythe vapors, and conduct the fornwr back to the still through the connection 515,

The treating tank D and pressure filter F are similar to the same elements D and F employed in the initial steps of the system,- the local pump connections and treating agent supply pipes being omitted to avoid overcrowding of the drawings'.

In carrying out the broad principles of my invention, I donot necessarily limit myself to the use of kieselguhr as the treating agent, although I prefer to use the same, or

its equivalent, as owing to its' diatomaceous or natural peculiar cellular formation, and 40 the further fact that it is light and highly y buoyant as a lpermeated oil laden vehicle, it is particularly adapted for use in the steps of .my process employingan inert pulver-- ized absorptive and filtrationymedium.

acteristic elements of'- the system and certain details thereof, I will now trace out the lines l,

of connections between thesev several elements, and later the functioning of the the prodessinvolved. t

57-58 is a pump line from the receiving ,50 whole svstem in carrying outv the steps of ftanks A to the defecators 'B, a' pump 59 bethe pipe 72 as shown..

Having thus generally outlined thcharf oil outlet pipe pipo69il discharges into the top of the tank D, as t rough a funnel opening 71.

72 is a pipe connection between the bottom of the tank D and the bottom of the first pressure filter F, and 73 is a pipe leading vfrom the top of the tank D, at the end opposite the inlet 68, and connecting with An auxiliary pump line is also shown, consisting of the pipe 74 leading from the bottom of the tank D to the suction chamber of a pump 75, the outlet pipe 76 of which connects with the pipe 72.

77 is a pipe conduit from the trough 53 of the pressure filter F to the clear oil containers G, in the initialsteps of process, and from the trough 53 of the filter F', following the step of distillation, from which latter filter the pipe 77 may lead to other treating tanks or filters, as desired, or to storage, for commercially packing in barrels or other containers.A v

78 is a pipe line, connected at one end, through a pump 79, to the bottoms of' the, containers G, and at its other end communieating, through the' branch 80, with the open .tops of the still supply tanks H, and also with the mixing receptacle E, through the extension pipe 81.

Below the still supply tanks H extends a branchpipe 82, with which there is connected valved outlets 83ffrom the respective still supply tanks.

, A singleconduit pipe 84 leads from the branch' supply 82 into the bottom of the still K. A

85 is. a valved connection, providing for vthe discharge'of the residual oil from the still to the oilstorage tanks N, and 86 is a valved Vpipe leading from the residual oil storage tanks N to the inlet 68 of the treating tank D', inthe same vsubstantial relation as the oil branch pipe 64, excepting that the'supply of oil is now from the tanks N and not from the flotation separator C which is not employed after distillation.

Also the other connections with and from this treating tank D are the same and have, therefore, been numerically designated as previously-described with reference tothe.

treating tank D and pressure lter F, with the exception that the treating mixture pipe lines 69 and 70 have been omitted, as welly as the pump connections 74-75-7 6, for the reasons before stated Sil 87 is an outlet from the Worm coil of the condenser, and While not illustrated with reference to the refinement of lubricating oils, as a matter of actual practice, this outlet 87 leads to a similar treating and liltering process, as before described with reference to the lubricating oils, so that the condensed vapors or highly volatile petroleum distillates, in the nature of naphtha, are also conserved as a valuable reiined commercial product.

In the arrangement shown in Fig. 2, the dotation separatorl C is disposed between the treating tank and pressure filter, the Yali'ed outlet pipe S8, leading from the top of the tank D, and the Valved branch 8f), leading from the bottom thereof, communicating vwith the combined oil and water inlet. of the dotation separator C, While the oil outlet pipe elle from the latter is connected, through the pipe 90, with the bottom ot the pressure lilter. Otherwise the functioning of the system is substantially the same in both instances.

These Yvarious pipe lines and branches, as just described, are suitably provided with controlling Valves, as shown, and certain ot these valves, hereinafter more specifically referred to, have been designated by the reference numerals 1 to 17, inclusive.

In operation, the valve 1 being opened and the pump 59 started, the impure oil ispumped up from the tanks A, through the pipe line 57-58, to the detecators B, Where it is first highly heated, as by steam coils 3e, and allowed to settle..

li: acidity-appears in the oil, milk of lime, or its equiyalent, may be introduced into the defecators as a neutralizing agent, or any other suitable defecating agent, as desired, may be employed generally tor clarification purposes.

ABetere subjecting the partially detecated oil to further treatment, with the valve 3 open l,and the valves 2 and et closed, any7 supernatant clear oil may be deeanted ott from desired levels in the deteeators (Without passing through the entire system) by way'of the Valvedbranches 60, the upper portion of the pipe line 61, branch 62 and supply conduit 63, from which it is discharged into the clear oil containers G. Or if it is desired to Wash the deeanted clear oil rst, to eliminate odors etc., with the Valves 3 and LlY closed and the valves 2 and 5 open, the decanted oil Will flow to the inlet 35, into and through the Water of the flotation separator C, thence out through the oil outlet.- pipe 4.4, the valve 6 being also open, and into Gthe conduit 63, leading tothe containers To pass the remaining contents of the defecators through the whole initial treating system, the valves 2 and 6 being closed and the valves 4, 5 and 7 opened, the flow from bottom ot the defecators will be through the branch 6T, the lower line `61, the inlet 35, and through the Water of the flotation separator, the Washed oil passing thence through the pipes le'and Minto the treating tank D at the inlet G8.

At the same time Water, preferably heated, is supplied to the flotation separator .trom the Water pipe 65the valved connection being open, through the combined oil and Water inlet 35. v

in passing through the flotation separator` the oil substantially follows the course indicated by the main arrows, the heavier impurities Washed out being precipitated and battled to the bottom of the tank, and the floated or supernatant Washed oil itselt, overlowing intothe open cup 42, thence through the elbow 43 and oil outlet pipe r1 as mentioned, 'While the excess Water is deflected around through the channel 40, and discharges above the oyeriiow 41 into the Wastel Water outlet pipe 36, the top of the oi-'eri'ion' located slightly below the open top of the cup i2 preventing the Water :trom reaching the level of the open top of the cup il?, and hence Water Will not How-out n'ith the oil. Y Y also, with the valves 8 and 9 open and the yali'e 1() closed, the kieselguhr,or other substantially equivalent treating agent, mixed with clean oil, is caused to How, through the pipe 69 and inlet GS, into the treating tank D at its bottom, While with the Valve 9 closed and the valves S and 10 open, the discharge ot the treating mixture is in through the top or" the treating tank, which is oftentimes desirable.

in the treating tank D the partly defecated and `Washed oil and the treating mixture are thoroughly agitated to cause an intima-te commingling of same, resulting in a conglomerate freely iowing mass.

lWhen the treatment in the tank D is to be continuous, the valves-11, 18 and 1e are closed and the valve 12 opened, when the mixture passes through the outlet pipe and the pipe 7 2 into the bottom of the pressure lilter F, TVliere the treatment is not continuous, but in charges, the valves 12, 13 and la are closed and the valve 11 opened, whereupon the iiow of the mixture is directly through the pipe 7 2 into the pressure filter. And finally, in eases Where the pressure froml the inside and the outside of the lilter is so equalized that the flow there` through is diminished or retarded, the valves 11 and 12 are closed and the Valves 13 and 14 opened, so that upon operation of the pump 75, the mixture is sucked from the the tank D and forced' positively ino into the pressure lilter by Way ot the lower pipe line 72.

Up to the point of filtration through the pressure lter F, thekieselguhr has acted upon the impregnating entrained oil to absorb in a large measure its colloidal and coloring substances, and it now becomesl necessary to separate the oil from the kieselguhr and the remaining insoluble suspended impurities.

During the operation of filtration through A the pressure filter F, Whether the delivery thereto is by gravitation or forced feed, it is obvious that the flow ofthe treating agent will become obstructed and halted, butl as the kieselguhr is very buoyant and does not settle, it gradually forms as a thickened surface exteriorly ofthe'filter frames.

Instead` however, of clogging up and retarding filtration through the pores of the filter cloth bags, it acts reversely and itself becomes an extremely eliective physical agency of separation, its innumerable Walls of irregular microscopic cells providing an enormous area of filtering surfaces, as is understood, and the oil seeping through this sponge like porous mass is substantially freed from all carbonaceous and other insoluble matters, while the kieselguhr itself,

with its absorbed gummy matters and other impurities, is halted in its flow, the filtered oil passing 11p and o through the drip spouts 52, of the filter frames, into the trough 53, from whence it is led, by the pipe 77, to the clear oil containers, as a substantially purified and clarified liquid.

While the oil is now substantially free of colloidal and general organic .and inorganic impurities, it still contains a large percentage of naphtha and similar volatile con. stituents, very deleterious to the same for thehighest lubricating efliciency. l

The second phase, therefore, of the present improved process, and perhaps the most important step thereof, resides in the elimination of these harmful volatile constituents.

In the accomplishment of this, the now clear oil is led into a still, suitably heated to avoid cracking distillation so that vaporization ofthe lighter volatile constituents is effected as speedily as possible, Without any of the vapors condensing in the still and oil and after distil is set so that the feed of vfresh oil to the falling'back into the body of the oil. The oil may first be pumped up through the pipe line 78 and branch 80 into the still supply tanks H, the valve 15 being opened and the valve 16, in the extension 81, closed. It may also be' conveniently stated here that, if it is desired to Ell the mim'ng rece tacle E with clean oi-l, this Imay readily e done by closing the valve 15 and opening the valve 16, as will be apparent.. From the still sup ly tanks H the bottom of the. still is parta y 'filled'with theA clear lation has progressed sufiiciently to pass' ofi' as vaporsjthe lighter distillates through the vapor line 54 and condenser coil 55, the valve 17, inthe linesi simply mean .includes t may be regulated as desired, the hot oil in the still serving to immediately vaporize off the lighter volatilizable constituents of the inflowing oil.

When the still finally becomes filled to the level desired, the valve 17 is shut off and the heavier distillates arel gradually vaporized off also, until the residue oil has attained the flash andfire points desired, all as set forth fully in my oil still application before mentioned.

After the still is shut down, its contents may then be drawnl olf, into the residual oil storage tanks N, through the valved outlet 85. l The oil as a lubricant is now in excellent condition, being relieved substantially of most impurities as Well yas the naphtha distillates, but in order to still further improve the same, l nd that extreme beneficial results are attained' by further treatment after distillation, as extreme purifying action seems to be more effective after distillation. This may be in part accomplished by suitable filtration alone, although perfection is more nearly approached by conducting the residual oil through the steps initially ap nlied, to the partially defecated oil, with yre erence to treatment with kieselguhr and subsequent filtration. This needs no further explanation, although the tank D and pressure filter F are illustrated asa means for carrying out these final steps. t

Obviously the pipe 77 from the lter -F may lead to storage or to further treating or filtering means, until such continued treatments result inthe oil becoming practically pure White. This however, would petition o'l'2 the first steps of treatment an filtration after distillation, and would therefore add no additional ndvelty to the process. v

While l have thus disclosed my process and a practical system for carrying out the same, l do not limit myself to minor details, i

the process and apparatus not being rno stricted, excepting as limited by the scope of. theensuing claims, viewed from a fair standpoint of the doctrine of equivalents.

For this reason, the arrangement of the tank D,Votation separator C and pressure '11.5 filter F, as shown in FigLQ, is not deemed to be substantially different from that shown in Fig. 1. v v I Y What l claim as new` and patentable, is

1. The process ofreclaiming oils, which 12o includes the step of treating the impure oil `with an inert pulverized absorbent medium to initially relieve it of its foreign impurities; subsequently distilling from the clarit fied anduried oil its naphthas and finally 126 subjecting the residue product, as relieved of its naphtha constituents, to further treatment by iiltratio'n, substantially as described.

2. The process of reclaiming oils, which e step of thoroughly combining@ 18e proportionate amount of an inert pulverized absorbent medium With the .impure oil to provide a conglomerate freely flowing mixture; then causing said mixture to flow into association with a retarding filtration agency, the flow ot said treating substance and substantially colloidal and other foreign impurities being halted by said filtration agency as the oil nercolates therethrough; and subsequently distilling from the clarified and purified oil its naphthas, substantially as described.

3. The process ot reclaiming oils, which includes the step oi thoroughly combining a proportionate amount of a suitable treating substance7 substantially as set forth, with the impure oil to 'provide a conglomerate Jfreely flowing mixture; then causing said mixture to iow into association with a retarding filtration agency, the flow' of said treating substance and substantial colloidal and other foreign impurities being halted by said filtration agency as the oil percolates therethrough; subsequently distilling from the clarified and purified oil its naphthas; and tinally subjecting the residue product, as relieved of its naphtha constituents, to further treatment by filtration, substantially as described,

4. rlhe process of reclaiming oils, which includes the step of treating the impure oil to initially relieve it of its substantial toreign impurities; subsequently distilling l'roni the clarified and purified oil its naphthas; then combining a proportionate amount of an inert pnlverized absorbent mediam with the residue oil, as relieved ot its naphtha constituents, toprot/*idea conglomcrate freely dowing mixture; and finally causing said mixture to flow into association with a retarding ltration agency, the lion' ot said treating substance and substantial remaining impurities being halted as the oil percolates through said iiltration agency in a refined state substantially as described.

I 5. 7lhe process of reclaiming oils, which includes the initial steps of Washing and treating the impure oil with an inert pulyerized absorbent medium, to proride a 'freely flowing conglomerate mixture ot the halted by said filtration agency as the oil'l percolates therethrough in a substantially clarified and purified state: and finally distilling its naphthas from the clarified and purified oil, substantially as described.

G. 'lhe process of reclaiming oils, which includes the steps of initially heating the impure oil in a defecator, a suitable defecating agent being introduced as desired; then treating the partly defecated oil by passing the same through the water of a flotation separator and adding thereto a proportionate charge of an inert pulverized absorbent medium, to provide a freely flowing conglomerate mixture of the oil and treating substance, With the odors and heavier impurities washed out; then ,flowing said conglomerate mixture into association with a retarding filtration agency, the lion? of said treating substance and substantial colloidal and other foreign impurities being halted by said filtration agency as the freed oil percolates therethrough in a highly detecated state; and finally dist-illing from said defecated residue oil its naphthas, substantially as described.

7. ln a system for reclaiming oils2 the combination of a treating tank for receiving the impure oils in conjunction with a proportionate amount of a suitable treating substance substantially as set forth; a filter tanlr suitably coupled up in communication with said treating tanlr and containing filtering means permitting of the percolation ot oil therethrough While halting the den' of Said treating substance and other impurities; a still suitably coupled up with the pure oil chamber of said filter tanlr; a Vapor line leading ott from said still; and means for further filtering the contents ot said still after distillation, substantially as described.

ln testimony whereof, l ax my signature.

OlilVllR C. SWAN. 

